Flaked cereal are typically produced by cooking coarse grain materials, such as corn grits, together with water, steam, and optionally one or more of flavor, appearance, and texture-influencing ingredients, such as sugar, malt extract, and salt, using a rotary cooker. The cooked coarse grain material is then partially dried. After it is partially dried, the partially dried grain material may be optionally tempered, meaning the partially dried grain material is allowed to rest for a certain period of time. The partially dried grain material is then flaked into thin slices by use of a flaking mill and toasted, wherein the flaked grain material is further dried and partially browned using a toaster oven.
An alternative method for producing flaked cereal is by feeding milled grain material, such as corn meal or flour, into the feed section of a cooking extruder, mixing said corn meal or flour with water, optionally steam, and optionally one or more other flavor, appearance, and texture-influencing ingredients such as sugar and salt, and cooking the food material to at least partially gelatinize the starch component of the food material inside the cooking extruder. The cooked food material is then transferred to a forming extruder via a connecting closed pipe, wherein the cooked food material inside the forming extruder is cooled to a temperature below 212° F., extruded through one or a multitude of die orifices of a given shape, preferably a round shape, and cut by the use of a cutting knife assembly. The cut food material pieces are then transferred to a dryer and partially dried. After they are partially dried, the partially dried cut food material pieces may be optionally tempered, meaning the partially dried cut food material pieces are allowed to rest for a certain period of time. The partially dried cut food pieces are then flaked into thin slices by use of a flaking mill and toasted, wherein the flaked grain material is further dried and partially browned using a toaster oven.
The method described above can be optionally enhanced by using a pre-conditioner to mix the milled grain material with all other above-mentioned ingredients prior to feeding the material into the cooking extruder. The method described above can be optionally further enhanced by performing the cooking, cooling and forming of the food material by only a cooking extruder, without transfer to and use of a separate forming extruder. This can be accomplished by use of a vent port in a section of the cooking extruder.
Both above-mentioned methods for producing flaked cereal involve the use of at least four unit operations, most commonly the use of five or six unit operations, and the addition and removal of large quantities of water, most commonly the addition of water to about 27 to 35 percent of the total mass of the cooked food material. Both of the above-mentioned methods also involve a significant amount of time for the treatment of the food material, commonly involving at least 30 minutes of total processing time and most commonly about one hour. When a tempering step is added to the process, the total processing time can extend up to a total of two hours or more.
In other examples, a simplified version of the second of the two methods described above is presented, in which the cooked cereal dough is cold-formed into slices of the thickness of the desired final flake product, eliminating the need for using a flaking mill. However, this method still requires cooking the grain material at a relatively high moisture content of between 20 and 30 percent, cooling the cooked grain material to a temperature below 212° F. via the use of a cold-former or the use of a cooling section with a vent port to avoid puffing of the sliced cereal pieces, and performing a secondary drying step after toasting of the cold-formed cereal slices to reduce the moisture of the finished cereal pieces to a shelf-stable level of typically less than three percent.
Like reference symbols in the various drawings indicate like elements.